Hasil untuk "General. Including alchemy"

David Encinas-Basurto, Kiley McCombs, Ernest L. Vallorz et al.

Swellable microparticles are a promising strategy for pulmonary drug delivery. They provide good aerosol performance in the dry state and enlarge after deposition in the lungs. In this study, we aimed to develop and characterize spray-dried microparticles composed of carboxymethyl chitosan (CMC), L-leucine, and suramin, a hydrophilic polyanionic drug. Microparticles were obtained by co-spray drying (Co-SD) formulations with increasing leucine content (0–10% <i>w</i>/<i>w</i>) and evaluated for morphology, thermal behavior, crystallinity, swelling, aerodynamic deposition using a Next Generation Impactor (NGI), and cytocompatibility in pulmonary epithelial cells. The 10% leucine formulation produced the highest fine particle fraction (35.2 ± 1.1%) and the lowest mass median aerodynamic diameter (1.0 ± 0.4 µm). These values indicate efficient in vitro deep lung deposition. XRPD and DSC showed that the Co-SD formulations were predominantly amorphous. Hydration studies revealed rapid water uptake and a clear increase in particle size, leading to the formation of swollen microgels. Cell viability assays demonstrated >85% viability up to 100 µM suramin, suggesting that CMC–leucine microgels enable efficient pulmonary delivery of hydrophilic drugs by combining respirable dry-state properties with in situ swelling and reducing immunological clearance. Future in vivo studies will be needed to assess long-term stability, macrophage interaction, and the translational potential of this delivery system.

Guanghui Liu, Jingchao Fan, Li Wang et al.

This study investigated the changes in pH, water retention, color, texture characteristics, protein conformation, thiobarbituric acid reactive substances (TBARSs), total volatile basic nitrogen (TVB-N), and total plate count in reduced-fat sausages. It explored the quality differences between sausages with and without the addition of resistant starch during storage at 4 °C over a period of 1 to 30 days. The results indicated that TBARS and TVB-N values significantly increased (<i>p</i> < 0.05) with the extension of refrigeration time, and the α-helix and β-sheet structures were transformed into β-turn and random coil structures, leading to a significant decrease in the pH, <i>L*</i> and <i>a*</i> values, texture characteristics, and chewiness of all sausages, as well as a significant increase in storage loss and centrifugation loss. Under the same refrigeration time, the sausage with added resistant starch exhibited better water retention and texture characteristics compared to the treatment without resistant starch. Additionally, the TBARS and TVB-N values were significantly lower (<i>p</i> < 0.05) in the former. Therefore, the incorporation of resistant starch can effectively slow down the deterioration of gel properties and the increase in total bacterial count in reduced-fat sausages during refrigeration.

Itzel Nevarez-Rico, Guillermo Ignacio Guangorena-Zarzosa, Takaomi Kobayashi et al.

Pineapple fibers were used as a sustainable raw material to isolate native cellulose from alkaline–acid treatment. The cellulose fibers were regenerated into transparent and flexible cellulose hydrogels using the lithium chloride/N,N-dimethylacetamide (LiCl/DMAc) solvent system, followed by a phase-inversion process of the cellulose solution under ethanol vapor. Chlorhexidine was incorporated into the hydrogels to provide antibacterial properties. The concentration of chlorhexidine ranged from 0.1 to 0.8 wt%. The prepared hydrogels showed better early onset cytocompatibility than the cell culture dish used as a control. For the evaluation of antibacterial properties, strains of <i>Streptococcus mutans</i>, <i>Streptococcus sanguis</i>, and <i>Streptococcus anginosus</i> were used. The results indicated antibacterial activity at all chlorhexidine concentrations tested, with the area of bacterial inhibition increasing with increasing bactericidal content in the hydrogel films. Adding bactericide into cellulose films did not compromise their early onset cytocompatibility in the first 72 h. The study suggests that adding chlorhexidine provides the hydrogel films with antibacterial properties, potentially expanding their applications in dentistry.

Shakila Parveen Asrafali, Thirukumaran Periyasamy, Jaewoong Lee

Polybenzoxazine-based aerogels are a unique class of materials that combine the desirable properties of aerogels—such as low density, high porosity, and excellent thermal insulation—with the outstanding characteristics of polybenzoxazines—such as high thermal stability, low water absorption, and superior mechanical strength. Polybenzoxazines are a type of thermosetting polymer derived from benzoxazine monomers. Several features of polybenzoxazines can be retained within the aerogels synthesized through them. The excellent thermal resistance of polybenzoxazines, which can withstand temperatures above 200–300 °C, makes their aerogel able to withstand extreme thermal environments. The inherent structure of polybenzoxazines, rich in aromatic rings and nitrogen and oxygen atoms, imparts flame-retardant property. Their highly crosslinked structure provides excellent resistance to solvents, acids, and bases. Above all, through their molecular design flexibility, their physical, mechanical, and thermal properties can be tubed to suit specific applications. In this review, the synthesis of polybenzoxazine aerogels, including various steps such as monomer synthesis, gel formation, solvent exchange and drying, and finally curing are discussed in detail. The application of these aerogels in thermal insulation and flame-retardant materials is given importance. The challenges and future prospects of further enhancing their properties and expanding their utility are also summarized.

Lin Huang, Qinjie Li, Yao Lu et al.

Alzheimer’s disease (AD) is a common cause of dementia, characterised by cerebral amyloid-β deposition, pathological tau and neurodegeneration. The prodromal stage of AD (pAD) refers to patients with mild cognitive impairment (MCI) and evidence of AD’s pathology. At this stage, disease-modifying interventions should be used to prevent the progression to dementia. Given the inherent heterogeneity of MCI, more specific biomarkers are needed to elucidate the underlying AD’s pathology. Although the uses of cerebrospinal fluid and positron emission tomography are widely accepted methods for detecting AD’s pathology, their clinical applications are limited by their high costs and invasiveness, particularly in low-income areas in China. Therefore, to improve the early detection of Alzheimer's disease (AD) pathology through cost-effective screening methods, a panel of 45 neurologists, psychiatrists and gerontologists was invited to establish a formal consensus on the screening of pAD in China. The supportive evidence and grades of recommendations are based on a systematic literature review and focus group discussion. National meetings were held to allow participants to review, vote and provide their expert opinions to reach a consensus. A majority (two-thirds) decision was used for questions for which consensus could not be reached. Recommended screening methods are presented in this publication, including neuropsychological assessment, peripheral biomarkers and brain imaging. In addition, a general workflow for screening pAD in China is established, which will help clinicians identify individuals at high risk and determine therapeutic targets.

Mii Fukuda Hayami, Takashi Menju, Takeshi Ide et al.

We have constructed an outer-cylinder-rotating Couette device for high-speed shear flow in laminar flow conditions and visualized the structure formation and subsequent rearrangement of PACl (flocculant made of aluminum hydroxide gel) and kaolinite flocs by visible light imaging. In a previous report, we analyzed the case of relatively low shear rate (<i>G</i>-value = 29 1/s) and confirmed that the flocculation process could be separated into two stages: a floc growth stage and a breakup/rearrangement stage. Once the large bulky flocs that reached the maximum size appeared, they rearranged and densified through structural fracture and rearrangement. In this report, this process was further investigated by conducting experiments under two different high shear rates (58 and 78 1/s) at which breakup and rearrangement became more pronounced, and three different aluminum kaolinite ratios (ALT ratios) that were over and under the optimum dosage (neutralization point by Zeta potential). Visualization results confirmed that, during the growth stage, the flocculation rate could be approximated by a scaling relationship between floc size and elapsed time, which depended on the ALT ratio. After reaching the maximum size, the floc rapidly became compact and dense following adsorption of the gel, incorporating fine fragments from erosion breakup. The over and under dosages created a lot of fragments of erosion breakup, but less so in the optimum dosage. In the optimum ALT ratio, fragments did not remain because they were incorporated into the flocs and densified, and the floc size was thought to be maintained. The floc circularity distribution peaked at around 0.6 and 1, suggesting that the flocs were spherical in shape due to erosion breakup.

Zhengdong Zhao, Yichang Jing, Yuan Shen et al.

The excessive emission of iron will pollute the environment and harm human health, so the fluorescence detection and adsorption of Fe³⁺ are of great significance. In the field of water treatment, cellulose-based gels have attracted wide attention due to their excellent properties and environmental friendliness. If carbon dots are used as a crosslinking agent to form a gel with cellulose, it can not only improve mechanical properties but also show good biocompatibility, reactivity, and fluorescence properties. In this study, silicon-doped carbon dots/carboxymethyl cellulose gel (DCG) was successfully prepared by chemically crosslinking biomass-derived silicon-doped carbon dots with carboxymethyl cellulose. The abundant crosslinking points endow the gel with excellent mechanical properties, with a compressive strength reaching 294 kPa. In the experiment on adsorbing Fe³⁺, the theoretical adsorption capacity reached 125.30 mg/g. The introduction of silicon-doped carbon dots confers the gel with excellent fluorescence properties and a good selective response to Fe³⁺. It exhibits a good linear relationship within the concentration range of 0–100 mg/L, with a detection limit of 0.6595 mg/L. DCG appears to be a good application prospect in the adsorption and detection of Fe³⁺.

K. Destounis, Giulia Huez, K. Kokkotas

Due to the growing capacity of gravitational-wave astronomy and black-hole imaging, we will soon be able to emphatically decide if astrophysical dark objects lurking in galactic centers are black holes. Sgr A*, one of the most prolific astronomical radio sources in our galaxy, is the focal point for tests of general relativity. Current mass and spin constraints predict that the central object of the Milky Way is supermassive and slowly rotating, thus can be conservatively modeled as a Schwarzschild black hole. Nevertheless, the well-established presence of accretion disks and astrophysical environments around supermassive compact objects can significantly deform their geometry and complicate their observational scientific yield. Here, we study extreme-mass-ratio binaries comprised of a minuscule secondary object inspiraling onto a supermassive Zipoy-Voorhees compact object; the simplest exact solution of general relativity that describes a static, spheroidal deformation of Schwarzschild spacetime. We examine geodesics of prolate and oblate deformations for generic orbits and reevaluate the non-integrability of Zipoy-Voorhees spacetime through the existence of resonant islands in the orbital phase space. By including radiation loss with post-Newtonian techniques, we evolve stellar-mass secondary objects around a supermassive Zipoy-Voorhees primary and find clear imprints of non-integrability in these systems. The peculiar structure of the primary, allows for, not only typical single crossings of transient resonant islands, that are well-known for non-Kerr objects, but also inspirals that transverse through several islands, in a brief period of time, that lead to multiple glitches in the gravitational-wave frequency evolution of the binary. The detectability of glitches with future spaceborne detectors can, therefore, narrow down the parameter space of exotic solutions that, otherwise, can cast identical shadows with black holes.

Dilyana Georgieva, Mariela Alexandrova, Sijka Ivanova et al.

Dexamethasone (DXM) is a highly potent and long-acting synthetic glucocorticoid with anti-inflammatory, anti-allergic, and immunosuppressive effects. However, the systemic application of DXM can cause undesirable side effects: sleep disorders, nervousness, heart rhythm disorders, heart attack, and others. In the present study, multicomponent polymer networks were developed as potential new platforms for the dermal application of dexamethasone sodium phosphate (DSP). First, a copolymer network (CPN) comprising hydrophilic segments of different chemical structures was synthesized by applying redox polymerization of dimethyl acrylamide onto poly(ethylene glycol) in the presence of poly(ethylene glycol) diacrylate (PEGDA) as a crosslinker. On this basis, an interpenetrating polymer network structure (IPN) was obtained by introducing a second network of PEGDA-crosslinked poly(N-isopropylacrylamide). Multicomponent networks obtained were characterized by FTIR, TGA, and swelling kinetics in different solvents. Both CPN and IPN showed a high swelling degree in aqueous media (up to 1800 and 1200%, respectively), reaching the equilibrium swelling within 24 h. Additionally, IPN showed temperature-responsive swelling in an aqueous solution as the equilibrium swelling degree decreased considerably with an increase in the temperature. In order to evaluate the networks’ potential as drug carriers, swelling in DSP aqueous solutions of varied concentration was investigated. It was established that the amount of encapsulated DSP could be easily controlled by the concentration of drug aqueous solution. In vitro DSP release was studied in buffer solution (BS) with pH 7.4 at 37 °C. The results obtained during DSP loading and release experiments proved the feasibility of the developed multicomponent hydrophilic polymer networks as effective platforms for potential dermal application.

M. Solovieva, Yuri Shatalin, I. Odinokova et al.

BACKGROUND Dithiocarbamates and derivatives (including disulfiram, DSF) are currently investigated as antineoplastic agents. We have revealed earlier the ability of hydroxocobalamin (vitamin В12b) combined with diethyldithiocarbamate (DDC) to catalyze the formation of highly cytotoxic oxidized derivatives of DSF (DSFoxy, sulfones and sulfoxides). METHODS Electron and fluorescent confocal microscopy, molecular biology and conventional biochemical techniques were used to study the morphological and functional responses of MCF-7 human breast cancer cells to treatment with DDC and B12b alone or in combination. RESULTS DDC induces unfolded protein response in MCF-7 cells. The combined use of DDC and B12b causes MCF-7 cell death. Electron microscopy revealed the separation of ER and nuclear membranes, leading to the formation of both cytoplasmic and perinuclear vacuoles, with many fibers inside. The process of vacuolization coincided with the appearance of ER stress markers, a marked damage to mitochondria, a significant inhibition of 20S proteasome, and actin depolimerization at later stages. Specific inhibitors of apoptosis, necroptosis, autophagy, and ferroptosis did not prevent cell death. A short- time (6-h) exposure to DSFoxy caused a significant increase in the number of entotic cells. CONCLUSIONS These observations indicate that MCF-7 cells treated with a mixture of DDC and B12b die by the mechanism of paraptosis. A short- time exposure to DSFoxy caused, along with paraptosis, a significant activation of the entosis and its final stage, lysosomal cell death. GENERAL SIGNIFICANCE The results obtained open up opportunities for the development of new approaches to induce non-apoptotic death of cancer cells by dithiocarbamates.

Runmiao Yang, Wei Jin, Chingcheng Huang et al.

A new azobenzene-based symmetric amphiphile was synthesized and characterized using ¹H NMR spectroscopy. Its self-assembly behavior as well as photo-responsive behavior in its solution and gel states were investigated. Such a compound can self-assemble into fiber mesophases in water solvent. After irradiation of the gels with UV light, the <i>trans</i> isomer of the compound rapidly photoisomerized to the <i>cis</i> isomer, which resulted in a rapid destruction of the gel. High temperature also caused a rapid drop in viscosity. To verify the antimicrobial activity of the hydrogel, live and death assays of human fibroblasts L929 properties were used for in vitro cell viability studies. The compound was converted to the terminal tertiary amine in a quaternary ammonium salt molecule by using hydrochloric acid. This azobenzene quaternary ammonium salt has a relatively better antimicrobial effect biocidal activity that was demonstrated when challenged against Escherichia coli on in vitro conditions.

Fayaz Ali, Imran Khan, Jianmin Chen et al.

Recently, hydrogels have been investigated for the controlled release of bioactive molecules, such as for living cell encapsulation and matrices. Due to their remote controllability and quick response, hydrogels are widely used for various applications, including drug delivery. The rate and extent to which the drugs reach their targets are highly dependent on the carriers used in drug delivery systems; therefore the demand for biodegradable and intelligent carriers is progressively increasing. The biodegradable nature of hydrogel has created much interest for its use in drug delivery systems. The first part of this review focuses on emerging fabrication strategies of hydrogel, including physical and chemical cross-linking, as well as radiation cross-linking. The second part describes the applications of hydrogels in various fields, including drug delivery systems. In the end, an overview of the application of hydrogels prepared from several natural polymers in drug delivery is presented.

Shishuai Wang, Shuo Chen, Lidong Ding et al.

The impact of konjac glucomannan (KGM) with different molecular weight (Mw) on the retrogradation properties of pea starch, such as color, viscoelasticity, gel strength, water holding capacity (WHC), moisture distribution and crystallinity, was investigated. At the same time as the Mw of KGM decreased, the lightness, elastic modulus, gel strength, water freedom and crystallinity of pea starch showed an increasing trend, whereas the viscosity modulus and WHC showed a decreasing trend. At one day of storage, compared with single pea starch, KGM with low Mw made gel strength increase from 40 g to 45 g, WHC decrease from 82% to 65% and crystallinity increase from 21.3% to 24.0%. Therefore, KGM with low Mw could promote retrogradation of pea starch in the short-term. At 7 days or even 14 days of storage, KGM with medium-high Mw had smaller indices than those of pure pea starch, including the lightness, storage modulus, gel strength, water freedom and crystallinity. This indicated that KGM with medium-high Mw could inhibit the long-term retrogradation of starch. The larger the Mw of KGM, the more noticeable the inhibition effect.

Diana Elena Ciolacu, Daniela Rusu, Raluca Nicoleta Darie-Niţă et al.

Novel hydrogels were prepared starting from different cellulose allomorphs (cellulose I, II, and III), through a swelling stage in 8.5% NaOH aqueous solution, followed by freezing at low temperature (−30 °C), for 24 h. After thawing at room temperature, the obtained gels were chemical cross-linked with epichlorohydrin (ECH), at 85 °C. The swelling degrees of the hydrogels were investigated, and a complex dependence on the type of the cellulose allomorph was found. Moreover, the gel stage has been shown to play a key role in the design of hydrogels with different performances, following the series: H-CII > H-CI > H-CIII. The correlations between the allomorph type and the morphological characteristics of hydrogels were established by scanning electron microscopy (SEM). The hydrogel H-CII showed the biggest homogeneous pores, while H-CIII had the most compacted pores network, with small interconnected pores. The rheological studies were performed in similar shear regimes, and a close correlation between the strength of the gel structure and the size of the gel fragments was observed. In the case of hydrogels, it has been shown that H-CII is softer, with a lower resistance of the hydrogel (G′) above the oscillation frequencies tested, but it maintains its stable structure, while H-CIII has the highest modulus of storage and loss compared to H-CI and H-CII, having a stronger and more rigid structure. The X-ray diffraction (XRD) method showed that the crystalline organization of each type of allomorph possesses a distinctive diffraction pattern, and, in addition, the chemically cross-linking reaction has been proved by a strong decrease of the crystallinity. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy provided clear evidence of the chemical cross-linking of cellulose allomorphs with ECH, by the alteration of the crystal structure of cellulose allomorphs and by the formation of new ether bands.

Shuaishuai Wei, Ying Gao, Lulu Ma et al.

Composite gels prepared with ovalbumin (OVA) as basic materials have been gradually utilized in food and biological fields. However, the structure and function of gels made from natural materials are not perfect, especially the hardness, viscoelasticity and water-holding capacity of gels, which are easily affected by various factors (pH, NaCl, etc.). In order to improve the antibacterial effect and safety of gels, and on the basis of exploring the bacteriostatic formula of lysozyme-oregano essential oil (LZ-OEO), the influence of microwave treatment on the stability of the composite bacteriostatic material gel was emphatically investigated and discussed so as to develop a new bacteriostatic gel material. The results revealed that the LZ-OEO antibacterial gel prepared by adding 20% OEO, with a ratio of 3:2 between OVA and LZ, was more stable after microwave treatment, and the synergistic antibacterial effect was significantly improved. That is, the OVA and LZ-OEO composite gel processed using a 350 W microwave treatment for 1 min had the highest hardness, the water-holding capacity reached 78.05% and a dense and ordered network structure was formed. In addition, the compound gel displayed excellent antibacterial effects against <i>Staphylococcus aureus</i> and <i>Escherichia coli</i>. The experimental findings in this study effectively expands the application scope of lysozyme antibacterial materials and provides a more favorable technical foundation for future development and utilization.

Lorenzo Bonetti, Andrea Fiorati, Agnese D’Agostino et al.

Infection is a severe complication in chronic wounds, often leading to morbidity or mortality. Current treatments rely on dressings, which frequently contain silver as a broad-spectrum antibacterial agent, although improper dosing can result in severe side effects. This work proposes a novel methylcellulose (MC)-based hydrogel designed for the topical release of silver nanoparticles (AgNPs) via an intelligent mechanism activated by the pH variations in infected wounds. A preliminary optimization of the physicochemical and rheological properties of MC hydrogels allowed defining the optimal processing conditions in terms of crosslinker (citric acid) concentration, crosslinking time, and temperature. MC/AgNPs nanocomposite hydrogels were obtained via an in situ synthesis process, exploiting MC both as a capping and reducing agent. AgNPs with a 12.2 ± 2.8 nm diameter were obtained. MC hydrogels showed a dependence of the swelling and degradation behavior on both pH and temperature and a noteworthy pH-triggered release of AgNPs (release ~10 times higher at pH 12 than pH 4). ¹H-NMR analysis revealed the role of alkaline hydrolysis of the ester bonds (i.e., crosslinks) in governing the pH-responsive behavior. Overall, MC/AgNPs hydrogels represent an innovative platform for the pH-triggered release of AgNPs in an alkaline milieu.

N. Sial, S. Saeed, Mukhtiar Ahmad et al.

Introduction Cancer is one of the most common malignancies and the leading cause of death worldwide. As a member of the transmembrane emp24 domain (Tmed)/p24 family of proteins, TMED2 expression variations have been documented earlier in only a few subtypes of human cancers, and the multi-omics profiling of TMED2 as a shared biomarker in different other subtypes of human cancers remains to be uncovered. Methods In the current study, TMED2 multi-omics analysis in 24 major subtypes of human cancer was performed using different authentic online databases and bioinformatics analysis including UALCAN, Kaplan–Meier (KM) plotter, Human Protein Atlas (HPA), GENT2, MEXPRESS, cBioportal, STRING, DAVID, TIMER, and CTD. Results In general, the TMED2 expression in 24 major subtypes of human cancers was higher relative to normal controls and was also strongly associated with the lower overall survival (OS) and relapse-free survival (RFS) duration of CESC, ESCA, HNSC, KIRC, LIHC, and LUAD patients. This implies that TMED2 plays a significant role in the development and progression of these cancers. Furthermore, the TMED2 overexpression was also correlated with different clinicopathological features of CESC, ESCA, HNSC, KIRC, LIHC, and LUAD patients. TMED2-associated genes network was involved in 3 diverse pathways, and finally, few stronger correlations were also explored between TMED2 expression and its promoter methylation level, genetic alterations, and CD8+ T immune cells level. Conclusion In conclusion, via this in silico study, we have elucidated that TMED2 can serve as a shared diagnostic and prognostic biomarker in CESC, ESCA, HNSC, KIRC, LIHC, and LUAD patients of different clinicopathological features but, further in vitro and in vivo research should be carried out to confirm these findings.

Lisa Parker, Rebecca Ryan, Suellen Young et al.

BACKGROUND Doctor-patient communication is an important part of safe and effective medication use. There is a lot of evidence about good communication and recognition of several key features that are important when discussing medications. OBJECTIVE The aim of this article is to provide evidence-based guidance for general practitioner (GP) communication with patients about starting, reviewing or stopping oral medication. DISCUSSION Communication involves listening and asking, as well as imparting information. Creating space for discussions and encouraging patient involvement by asking questions are important. Doctors should deliver core content about why to take medication and actionable messages about how to do so. Regular summing-up and checks of patient understanding are important. Communicating benefits and harms can be facilitated by including numbers, if done carefully (include time periods, natural frequencies, absolute figures). Scheduling extra time, using written resources and enlisting support of pharmacist colleagues can assist with effective communication and help patients navigate the sometimes-confusing world of medications.

F. Toscano, E. O'Donnell, J. Broderick et al.